Expository notes

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The TeX papers are available here in DjVu,
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Other file formats may be available upon request.

Abstract Hamiltonian mechanics

An unorthodox approach to Hamiltonian mechanics.
Note in particular that time is a momentum
(see Time is imaginary below).
It all comes to the same thing, of course.

Black hole information paradox

Many people resolve the black hole information paradox
by simply denying the existence of a paradox:
They say that pure states really can evolve to mixed states.
This is in the Schroedinger picture.
Can this explanation work in the Heisenberg picture?
I argue that it can in this post
to
sci.physics.research.

Duality

Functional analysis with quaternions

A heavily edited transcript of a discussion with
John Baez
about how to do functional analysis with quaternions.
If you want to do quantum mechanics with quaternions,
this would be the underlying mathematics.
By the way, you should know that there are some minor errors in here.

Radon Nikodym Theorem

A proof of the Radon Nikodym theorem (for σfinite measures),
with application to the Lebesgue decomposition theorem,
using notation that lacks the spurious ‘d’s
that usually infest this subject.
This is from a guest lecture
in an introductory graduate-level course on measure theory.